Rather than registering all extensions on their behalf in
sbi_ecall_init(), introduce another extension callback and
invoke that instead. For now, implement each callback by
simply registering the extension, which means this patch
has no intended functional change. In later patches, extension
callbacks will be modified to choose when to register and to
possibly narrow the extension ID range prior to registering.
When an extension range needs to remove IDs, leaving gaps, then
multiple invocations of sbi_ecall_register_extension() may be
used. In summary, later patches for current extensions and the
introductions of future extensions will use the new callback to
ensure that only valid extension IDs from the initial range,
which are also available, will be registered.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
We have redundant semicolon at quite a few places so let's remove it.
Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
To support 64 bit firmware counters on RV32 systems, we implement
sbi_pmu_counter_fw_read_hi() which returns the upper 32 bits of
the firmware counter value. On RV64 (or higher) systems, this
function will always return zero.
Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
The "read a firmware counter" SBI call should only work for firmware
counters so let us replace sbi_pmu_ctr_read() with sbi_pmu_ctr_fw_read()
which works only on firmware counters.
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Some platforms such as hifive unmatched doesn't implement mcountinhibit
csr. However, it has hardware events that can be monitored using 2
hpmcounter it has (i.e. mhpmcounter3 & mhpmcounter4).
Currently, PMU extension disabled if mcountinhibit is absent. That's not
really necessary as long as the supervisor OS keeps track of the delta
value of the counters. Without mcountinhibit, the delta value won't be
entirely accurate because the counters are freely running. However, that
should be fine to produce an approximate counter value which can help
performance analysis. Perf sampling won't work though as sscof extension
is not present in hifive unmatched.
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
RISC-V SBI specfication 0.3 defines a PMU extension that allows supervisor
mode to start/stop/configure pmu related events. This patch implements
all of the functionality defined in the specification.
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
